Magnetic data storage media are commonly used for storage and retrieval of data, and come in many forms, such as magnetic tape, magnetic disks, and the like. Magnetic tape media remains an economical medium for storing large amounts of data. For example, magnetic tape cartridges, or large spools of magnetic tape are often used to back up large amounts of data for large computing centers. Magnetic tape cartridges also find application in the backup of data stored on smaller computers such as workstations, desktop or laptop computers.
In magnetic tape, data is typically stored as magnetic signals that are magnetically recorded on the medium surface. The data stored on the magnetic tape is often organized along data tracks, and read/write heads are positioned relative to the data tracks to write data to the tracks or read data from the tracks. As the number of data tracks increases, the data storage capacity of the magnetic tape likewise increases. However, as the number of data tracks increases, the tracks usually become narrower and more crowded on the surface of the data storage tape. Servo tracks are also commonly defined on magnetic media to provide reference points for tracking the location of data tracks.
A wide variety of heads have been designed to write data to magnetic media. Various heads have also been designed to read data stored on magnetic media. A magnetic data storage system often includes both write heads and read heads to facilitate the writing of information to the magnetic medium and readout of such information.